The present invention relates to a method and apparatus for ascertaining the bulk weight of tobacco or other particulate material which can be conveyed in the form of a continuous stream. More particularly, the invention relates to a method and apparatus for continuously ascertaining the bulk weight of a stream of particulate (granular, fibrous and/or sheet-like) material which moves lengthwise. Typical examples of materials which can be monitored in accordance with the present invention are various types and/or forms of tobacco including leaves, shreds, ribs, laminae and/or mixtures thereof.
It is often desirable to ascertain the specific weight and/or density of conveyed particulate material (for the sake of convenience, the material will be referred to as tobacco, with the understanding, however, that the method and apparatus can be practiced with equal or similar advantage in connection with the treatment of other types of granular, fibrous, sheet-like or analogous particulate materials). Furthermore, it is often desirable to ascertain variations in the density of tobacco; this enables the attendants in a processing plant (e.g., in a plant wherein tobacco leaves are subjected to primary treatment including shredding, changing the moisture content or the like) to reduce the likelihood of adversely affecting the quality of processed tobacco and/or eventual malfunctioning of the processing apparatus. At the present time, the fact that the density of tobacco has changed is recognized only upon detection of loss in quality of processed tobacco and/or as a result of detection of damage to a particular piece of equipment. Such belated determination that the density has changed is of little value.